\begin{lstlisting}
sage: LFSR = LFSRCryptosystem()
sage: PT = LFSR.encoding('The dog ate my assignment.'); PT
010101000110100001100101001000000110010001101111011001110
010000001100001011101000110010100100000011011010111100100
100000011000010111001101110011011010010110011101101110011
0110101100101011011100111010000101110
sage: LFSR.decoding(PT)
'The dog ate my assignment.'
\end{lstlisting}%link
